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Current trait-based indices of soil fauna for assessing soil quality rely on extensive knowledge of life history traits for hyper-diverse groups. We look at the effects of clear-cut forest harvesting and subsequent wood ash application on the free-living nematode community using trait-based indices and body size spectra. We test the hypothesis that body size is a unifying trait and that the body size spectra can be used to demonstrate changes in soil quality while overcoming taxonomic impediments. Undisturbed boreal forest floor soils were compared with clear-cut sites amended with zero, one-half calcium equivalent wood ash, equivalent calcium reintroduction, and twice calcium reintroduction. Total abundance, trait-based metrics for the Maturity Index, and two metrics of body size spectra were calculated. Nematode abundance was not a good indicator of soil disturbance, while traditional trait-based approaches (the summed Maturity Index) demonstrated predicted changes in community structure. Analysis of two types of body size spectra elucidated how the community had changed under disturbance, and revealed that smaller bodied organisms were lost under ash amended treatments compared to both clear-cut and undisturbed forest. Using the body size spectra for nematodes is a simple addition to current trait-based approaches that can supplement soil assessments for disturbance and quality without requiring taxonomic expertise. 相似文献
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本文探讨了生态文化旅游定位,和在生态旅游与渗透生态文化教育相结合的问题。并从生态文化基础设施建设和挖掘生态文化内涵等方面阐述了龙湖山国家森林公园的规划方法,并提出了森林公园生态文化建设规划原则,规划重点和布局等内容。 相似文献
35.
《Scandinavian Journal of Forest Research》2012,27(4):331-341
Artificial regeneration of Scots pine (Pinus sylvestris L.) has been applied to a variety of forest site in Lapland. Occasional failures in regeneration have been observed on sites with high soil moisture contents and originally dominated by Norway spruce (Picea abies (L.) Karst). Understorey vegetation was studied on four naturally pine-dominated and eight spruce-dominated sites to determine suitable indicator plants for assessing soil moisture regimes. Soil moisture contents were estimated using the in situ dielectric measurements with radar surface arrival detection targeted to a depth of 0-50 cm. The abundance and frequence of plant species were analysed using logistic regression. The most reliable indicators were found to be Stereocaulon and Cladonia lichens for the dry regime (θv<25%), and Polytrichum commune Hedw. and Carex globularis L. for the wet regime (θv>25%). It was concluded that the indicator plants found in this study provide an alternative to the traditional Finnish forest site type approach in recognizing high soil moisture regimes. 相似文献
36.
进入21世纪以来,中国奶业步入了快速发展期,规模化奶牛场经营管理的科学研究已经成为每个奶牛场经营管理者的必修课程和首要任务。本文对规模化奶牛场经营管理效能的相关影响因子进行了系统的综述,分析了规模化奶牛场经营管理的国内外研究现状、取得的成果以及存在的不足,并对未来我国规模化奶牛场经营管理的研究方向进行了展望。 相似文献
37.
森林对降水的影响概述 总被引:1,自引:0,他引:1
森林能否增加降水,这是植树造林、美化环境等工作中必然要考虑的问题。文章总结了国内外相关文献,就森林对降水的影响做了阐述。综合现有研究结果来看,森林对降水有无影响目前还没有普遍性的结论;对于局地森林对降水的影响应持保守态度,既不能说"有",也不能说"无"。明确的结论必须结合当地地形、天气、气候条件做具体的研究分析后才能得出,这样的结论才更科学,更具指导意义。因此关于宁夏植树造林是否对宁夏的区域气候产生影响,以及有什么样的影响,目前还不清楚。另外一个主要问题就是森林的尺度,即多大面积的森林才会对区域降水产生影响,因为如果森林的面积很有限,对区域降水的影响是否也很有限等等,这些问题都需要进一步深入研究和探讨。 相似文献
38.
王磊 《内蒙古林业调查设计》2013,36(1):121-123,100
21世纪是信息时代,在信息社会中,随着网络技术的不断发展,科学技术的迅速发展,特别是"3S"技术在林业上广泛应用,森林资源的科学管理和高效应用是非常重要的,传统的森林资源管理模式已经不能适应时代的发展,因此,实现信息化管理势在必行。 相似文献
39.
《Journal of Sustainable Forestry》2013,32(2-3):165-187
Summary It is some years now since forest decline was a major public concern in Europe and was one of the principal environmental issues around which international research programs were focused. A number of internationally coordinated activities were initiated in the 1980s and 1990s and have continued until now; these contributed significantly to our current understanding of forestry and to the way in which forestry policies have developed. In short, the concept of sustainable development has had an increasing influence and is now of immeasurable value in forest policy, with sustainable forest management well established as its guiding principle. This sequence of events is examined here. The extent to which understanding has advanced is remarkable; much has changed. Arguably this period gave the first indication of the extent to which forests and ecosystems globally are threatened by environmental change. On the basis of the last 20 years, it is tempting to conclude that we now have an effective institutional framework and have made excellent progress. However, some of the recorded ecosystem responses seem anomalous; there are surprises in system responses, e.g., the linkage between sulphur and nitrogen depositions and forest growth. Even more importantly some specific pollutant problems remain and will intensify, and climate change has become an environmental issue of overwhelming importance. 相似文献
40.
农机工业必须依靠科技创新走新型工业化道路 总被引:8,自引:1,他引:8
分析了农机工业在新形势下不能适应我国农业发展和全面建设小康社会要求的现状,指出走新型工业化道路势在必行;系统论述了农机工业走新型工业化道路必须依靠科技创新,提高农机企业的管理水平和农机产品的科技含量,提升市场综合竞争力,开发新型农机技术和产品,保持农机工业和现代农业的可持续发展,发展先进技术装备和劳动力资源相结合的组合技术等主要方向和任务;提出了建设农机科技创新体系、支持农机创新活动等政策性措施和建议。 相似文献